Ukrainian opposition leader Vitaly Klitschko has called for European leaders to slap sanctions on members of the government of President Viktor Yanukovych.

The former boxing champion issued the appeal on January 11 after riot police clashed with protesters overnight in Kyiv. At least 10 people were injured in the clashes outside of a courthouse in the Ukrainian capital, including former Ukrainian Interior Minister Yuriy Lutsenko.

"I am calling again on European politicians to consider this question as soon as possible. Only personal sanctions against those who are the backbone of the Yanukovich regime can stop this regime," Klitschko said in a video released by his UDAR party.

The violence came after a court in Kyiv sentenced three men to six years in jail for allegedly plotting to blow up a statue of Lenin in 2011.

Reports said around 10 protesters were injured in the violence. The Interior Ministry said 20 officers had been hurt.

Lutsenko’s wife and his Third Ukrainian Republic organization said Lutsenko had suffered a concussion and other injuries after being struck in the head.

RFE/RL's Ukrainian Service quoted his wife as saying on January 11 that he was still hospitalized in "moderate" condition.

Antigovernment protesters took to the roads of Kyiv in the evening on January 11 to protest the latest police action. Honking their horns, they drove by the headquarters of the riot police, or "Berkut."

Tensions remain high in Ukraine since President Viktor Yanukovych's abrupt decision late in November not to sign a deal with the EU, sparking some of the biggest protests in the country since the 2004 Orange Revolution.